Increased efficiency and reliability is achieved in an engine with a combustion chamber structured as detonation resonator with an outlet to an exhaust nozzle. The resonator is formed as an aspherical reflector symmetrical with respect to the engine axis. The engine uses gaseous fuels and a gaseous oxidizer in a single stage combustion process. A pyrolyzing chamber for hydrocarbon fuel. Pyrolizing is achieved by contact of fuel flow with heated back side of the reflector. A mixture of fuel and oxidizer is supplied into the combustion chamber through an annular supersonic injection system. To initiate detonation, these engines may have a detonation initiator formed as a tube plugged at the distal end and open at the end inserted into the combustion chamber and located along the axis of the engine. Detonation products ejected through the exhaust nozzle create thrust that pushes the engine in the opposite direction.

Rotor systems are driven by jet engines arranged at the tip of a rotor that includes a structure that turns on a rotational axis. A jet stream generated by a jet engine produces a thrust force orthogonal to a rotor radius to motivate rotation. Methods presented include those which take advantage of the intrinsic centrifugal forces present in the rotor to convey gaseous fuel to the engine. Liquefied fuel from a source reservoir is evaporated into a gaseous state and made subject to centrifugal force causing it to move radially outward to a detonation type jet engine. These methods further include special process for mixing fuel with oxidizer and treating fuel or/and fuel mixtures to improve their detonation capacity.

A pulse combustor system for reducing noise and/or vibration levels. The system includes a pulse combustor including a combustion chamber, an inlet pipe, an exhaust pipe, and a first fuel injector for injecting fuel into the combustion chamber. The pulse combustor has a fundamental oscillation mode and one or more additional oscillation modes. The system includes at least one pressure sensor for measuring a pressure inside the fuel combustor and/or a at least one fluid velocity sensor for measuring fluid velocity at the inlet pipe or at the exhaust pipe. A controller adjusts a rate of fuel supply to the pulse combustor if the measured pressure and/or the measured velocity is above a predetermined threshold value to reduce excitation of the one or more additional oscillation modes.

A pulse combustor system for reducing noise and/or vibration levels. The system includes a pulse combustor including a combustion chamber, an inlet pipe, an exhaust pipe, and a first fuel injector for injecting fuel into the combustion chamber. The pulse combustor has a fundamental oscillation mode and one or more additional oscillation modes. The system includes at least one pressure sensor for measuring a pressure inside the fuel combustor and/or a at least one fluid velocity sensor for measuring fluid velocity at the inlet pipe or at the exhaust pipe. A controller adjusts a rate of fuel supply to the pulse combustor if the measured pressure and/or the measured velocity is above a predetermined threshold value to reduce excitation of the one or more additional oscillation modes.

An acoustic compression engine that includes an air intake section adapted to intake a volume of air. The volume of air is mixed with fuel within the air intake section. The acoustic compression engine also includes a resonant chamber adapted to intake a volume of air mixed with fuel from the air intake section. Compression of the volume of air mixed with fuel occurs within the resonant chamber and compression of the volume of air and fuel mixture is based on combustion of compressed air and fuel mixture and a resonant cycle of the acoustic compression engine. The acoustic compression engine further includes at least one exhaust nozzle that controls an exit of exhaust of gas that includes the combustion products at a requisite pressure to yield a thrust.

An acoustic compression engine that includes an air intake section adapted to intake a volume of air. The volume of air is mixed with fuel within the air intake section. The acoustic compression engine also includes a resonant chamber adapted to intake a volume of air mixed with fuel from the air intake section. Compression of the volume of air mixed with fuel occurs within the resonant chamber and compression of the volume of air and fuel mixture is based on combustion of compressed air and fuel mixture and a resonant cycle of the acoustic compression engine. The acoustic compression engine further includes at least one exhaust nozzle that controls an exit of exhaust of gas that includes the combustion products at a requisite pressure to yield a thrust.

A vehicle propulsion system includes an air heating chamber that receives inlet air from an air intake chamber and provides thrust through an exhaust chamber. A battery powered pulse generator generates a pulsed electrical output signal. An amplifier amplifies the pulsed electrical output signal to provide an amplified pulsed power output signal to the air heating chamber. The amplified pulsed power output signal directly heats the inlet air to generate thrust through the exhaust chamber.

A vehicle propulsion system includes an air heating chamber that receives inlet air from an air intake chamber and provides thrust through an exhaust chamber. A battery powered pulse generator generates a pulsed electrical output signal. An amplifier amplifies the pulsed electrical output signal to provide an amplified pulsed power output signal to the air heating chamber. The amplified pulsed power output signal directly heats the inlet air to generate thrust through the exhaust chamber.

Rotating detonation engines are provided with various improvements pertaining to performance and reliability. Improvements pertain to, for example, a fluidic valve/premixing chamber, injection/swirl, flow control and turning, ignition, and cooling.

A pulsed detonation engine may include a detonation tube for receiving fuel and an oxidizer to be detonated therein, one or more fuel-oxidizer injectors for injecting the fuel and oxidizer into the detonation tube, one or more purge air injectors for injecting purge air into the detonation tube for purging the detonation tube, and an ignition for igniting the fuel and oxidizer in the detonation tube so as to initiate detonation thereof. The detonation tube has an upstream end, a downstream end, and an axially extended portion extending from the upstream end to the downstream end and having a perimeter. The fuel-oxidizer injectors and purge air injectors may be disposed at least along the axially extended portion. The ignition may include a plurality of igniters disposed at or near the perimeter of the axially extended portion, spaced about the perimeter, at or near the upstream end of the detonation tube.